Functional Safety

Modes of Operation of a SIF The demand mode of a Safety Instrumented Function (SIF) refers to the operational mode in which the SIF is activated only when a specific

The Safety Instrumented System Safety Lifecycle defines the necessary activities involved in the implementation of SIF occurring during a period of time that starts at the concept phase of a

The development of the SIS SRS is one of the most important activities of the whole SIS safety life cycle. It is through this specification that the user is able

Human Independent Protection Layers (IPLs) rely on operators to take action in response to alarms or during routine system checks to prevent undesired outcomes. While human performance is generally less

The safety lifecycle approach recognizes that there are two fundamentally different ways in which the SIS can fail to perform its intended function. These are known as random and systematic

A failure occurs when a device at some level (a system, a unit, a module, or a component) fails to perform its intended function. Each safety instrumented function (SIF) in

A Safety Instrumented System (SIS) is a control system consisting of sensors, one or more controllers (often referred to as logic solvers), and final elements. Another common name is an

What is a Safety Instrumented Function (SIF)? A Safety Instrumented Function (SIF) is a system designed to reduce risks associated with specific hazards by taking an automatic action when required

Safety Integrity Level (SIL) is a quantitative target used to measure the level of performance required for a safety function to achieve tolerable risk for a process hazard. Defined in